Falling in love sounds wonderful until you think about how falling ends. The speaker begins in a light, almost shrugging tone, "Funny how that whole 'love' thing works", and describes the fairy-tale hope of finding a Prince Charming or Princess. Then the poem picks up speed. Love arrives, and you fall "so hard / And so fast" that you never stop to think about what comes next.
The twist is in the last lines. The word "falling" is spaced out letter by letter, as if time is slowing down, and then "hitting the ground" is stretched even further across the page. The layout makes us wait for the impact the way the speaker, in the moment of falling, never could. The mood is wry and a little bitter, with real hurt underneath the casual voice. The speaker seems to be warning that the rush of love and the pain of heartbreak come as a package, and that the second part is easy to ignore until it lands.